public function getAverageForMarkNumber($mark_number = null)
{
if ($mark_number < $this->getCourse()->getCurrentPeriod() || is_null($mark_number) && $this->getCourse()->getIsClosed()) {
$c = new Criteria();
$c->add(CourseSubjectStudentPeer::COURSE_SUBJECT_ID, $this->getId());
$c->addJoin(CourseSubjectStudentMarkPeer::COURSE_SUBJECT_STUDENT_ID, CourseSubjectStudentPeer::ID);
if (!is_null($mark_number)) {
$c->add(CourseSubjectStudentMarkPeer::MARK_NUMBER, $mark_number);
}
$c->clearSelectColumns();
$c->addSelectColumn("SUM(" . CourseSubjectStudentMarkPeer::MARK . ") as sum");
$stmt = CourseSubjectStudentMarkPeer::doSelectStmt($c);
$sum = $stmt->fetchAll(PDO::FETCH_COLUMN);
return sprintf('%.4s', $sum[0] / CourseSubjectStudentMarkPeer::doCount($c));
}
}
